Conditional sentences ("If" sentence)

(the conditional sentence type I)

1. Structure

Clause 1 (the simple future) + if + Clause 2 (the simple present)

2. Usage and Examples

- Describe the possible now or in the future.

For example:

I’ll visit Ho Chi Minh city if I have time.
We’ll pass the exam if we work hard.

3. The basic variant

Clause 1 (might/do +V) + if + Clause 2 (the simple present)

→ to indicate the ability to objectively

Ví dụ: It’s sunny. We may get a headache if we go out without a hat.

Clause 1 (may/can + V) + if + Clause 2 (the simple present)

→ to indicate permission

Ví dụ: You can go home if you finish your test.

Clause 1 (must/should + V) + if + Clause 2 (the simple present)

→ to just ask, please.

Ví dụ: You must do exercises if you want to get good marks.

4. If….not…= Unless

Ex:
- I won’t visit you if I don’t have time

→ Unless I have time, I won’t visit you.

- We’ll go camping if the weather is fine.

→ Unless the weather is fine, we won’t go camping.

- If you miss seeing the first part of the film, you can’t say you understand it.

→ Unless you see the first part of the film, you can’t say you understand it.

Note : clause contains "unless" non-negatives.

B. (the conditional sentence type II)

1. Structure

Clause 1 (would + V) + if + Clause 2 (the simple past tense)

2. Usage and Examples

- Describe the non-existent in current or future

For example:

If it were cold now, we wouldn’t switch on the fans.
(but it’s hot and we have to switch on the fans)
I would fly if I were a bird.
(but I am not a bird and I can’t fly)

Note : We use "were" for all the house, do not use "was"

3. The basic variant

Clause 1 (might/ could + V) + if + Clause 2 (the simple past tense)

→ only possibility

Ví dụ: He might succeed if he tried

I could speak French well if I lived in France.

C. (the conditional sentence type III)

1. The basic structure

Clause 1 (would have + P2) + if + Clause 2 (the past perfect)

2. Usage and Examples

- The third conditional sentence is not true conditions in the past.

Ví dụ:
a. Miss Phuong wouldn’t have won the prize if she hadn’t attended the beauty contest.
(but the fact that she attended and she won the prize)
b. We would have got good marks if we had prepared our last lesson carefully.
(but the fact that we didn’t prepare our last lesson carefully and we didn’t get good marks).

3. The basic variant

Clause 1 (could have + P2) + if + Clause 2 (had + P2)

→ only the subjective permission.

Ví dụ:
I could have won a prize if I had taken part in the competition last week.
You could have gone to the cinema if you had finished your homework last night.

Clause 1 (might have + P2) + if + Clause (had + P2)

→ only objective possibility.

Ví dụ: The last crop might have been better if it had rained much.

D. (the mixed conditional sentence type II and III)

1. The basic structure

Clause 1 (would + V) + if + Clause 2 (had + P2)

2. For example:

If I had been born in town, I would like life there.
(the fact that I wasn’t born in town, so I don’t like life there now)
If I followed your advice, I would have a job now.
(the fact that I didn’t follow your advice, so I don’t have a job now)

3. But for + noun + condition type II, III
But for: if there is no ...

Ví dụ:
You help me everyday so I can finish my work.
→ But for your daily help, I couldn’t finish my work.
She encouraged him and he succeeded.
→ But for her encouragement, he wouldn’t have succeeded.
The teacher explained and we understood.
→ But for the teacher’s explanation, we wouldn’t have understood.

E. Island of the sentence conditions

1. I kind Conditions

• If the question is "Should" in clause if, the island "Should" to the question

If he should ring , I will tell him the news.
→ Should he ring, I will tell him the news.

• If the question is not "Should", we have to borrow "Should"

If he has free time, he’ll play tennis.
→ Should he have free time, he’ll play tennis.
If she comes early, we’ll start.
→ Should she come early, we’ll start.

2. Category II conditions

• If the sentence the verb "were" the island "were" on top.

If I were a bird, I would fly.
→ Were I a bird, I would fly.
They would answer me if they were here.
→ Were they here, they would answer me.

• If the sentence has no verb "were" the loan "were" and used "to V"

If I learnt Russian, I would read a Russian book.
→ Were I to learn Russian, I would read a Russian book.
If they lived in Australia now, they would go swimming.
→ Were they to live in Australia now, they would go swimming.

3. Conditions III
• Island verb 's past tense finish .

If it had rained yesterday, we would have stayed at home.
→ Had it rained yesterday, we would have stayed at home.
If he had trained hard, he would have won the match.
→ Had he trained hard, he would have won the match.

Note : in the form of negation, "not" is placed after the subject :

Had it not been so late, we would have called you.